Remembering our past: Functional neuroanatomy of recollection of recent and very remote personal events. Cerebral Cortex, in press

Rotman Research Institute, Baycrest Centre for Geriatric Care, 3560 Bathurst St., Toronto, Ontario, M6A 2E1, Canada.
Cerebral Cortex (Impact Factor: 8.67). 12/2004; 14(11):1214-25. DOI: 10.1093/cercor/bhh082
Source: PubMed


Functional magnetic resonance imaging was used to study brain regions implicated in retrieval of memories that are decades old. To probe autobiographical memory, family photographs were selected by confederates without the participant's involvement, thereby eliminating many of the variables that potentially confounded previous neuroimaging studies. We found that context-rich memories were associated with activity in lingual and precuneus gyri independently of their age. By contrast, retrosplenial cortex was more active for recent events regardless of memory vividness. Hippocampal activation was related to the richness of re-experiencing (vividness) rather than the age of the memory per se. Remote memories were associated with distributed activation along the rostrocaudal axis of the hippocampus whereas activation associated with recent memories was clustered in the anterior portion. This may explain why circumscribed lesions to the hippocampus disproportionately affect recent memories. These findings are incompatible with theories of long-term memory consolidation, and are more easily accommodated by multiple-trace theory, which posits that detailed memories are always dependent on the hippocampus.

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Available from: Morris Moscovitch, Jul 06, 2014
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    • "Other regions identified in this analysis are associated with processes that are also likely to be involved in generating dialogic scenarios. For example, right MTG has been associated with accurate and confident recall (Chua et al., 2006, Giovanello et al., 2010), while the right precuneus has been associated with retrieval of verbal episodic memory (Fernandes et al., 2005), context-rich autobiographical memories (Gilboa et al., 2004) and first-person perspectives memories (sometimes called 'field' memories; Nigro and Neisser, 1983; Eich et al., 2009). The activation of cingulate gyrus for vividness ratings, though likely not specific to this process, has been linked previously to a right anterior insula network involved in affective engagement (Touroutoglou et al., 2012). "
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    Social Cognitive and Affective Neuroscience 07/2015; DOI:10.1093/scan/nsv094 · 7.37 Impact Factor
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    • "The inter-group comparison revealed that the older adults recruited the bilateral precuneus more in both positive and negative memories in contrast to the younger group. The precuneus was reported to be correlated with ratings of vividness (Gilboa et al., 2004) and play a key role in visual imagery processing in episodic memory recall (Fletcher et al., 1995; Cabeza and St Jacques, 2007). As our behavioral results showed that older adults recalled autobiographical memories more vivid than the younger adults, it is reasonable to observe greater activity in the precuneus of the older group than the younger group. "
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    • "Specifically, because facts are especially relevant to one’s everyday life, they may be preferentially associated with recent memories. We know that recent memories compared with past memories are associated with greater activity in the PMC (D’Argembeau et al., 2008; Gilboa, 2004; Söderlund et al., 2011) and in the MPFC (D’Argembeau et al., 2008). "
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